4WD work on ramp

[KJT]

While on a mechanics ramp, my 3.0TD surf is not spinning it's front wheels when low range or 4WD is selected. Is this normal? Will they only work when the wheels are on the ground?

The car performed as if it was working ok in the winter snow. I hope I've got somthing wrong here.

Any help would be most appreciated.

[TonyN]

you should have something spinning, if only the prop and one wheel.

is your front propshaft going round?

turn it off, hold the prop firm and spin one wheel, the other one should go in the opposite direction if the ADD is working properly.

[KJT]

Add?

Sorry, but what is the ADD? Could the hubs be unlocked/locked? (I've heard this phrase mentioned before but I don't know if this is right or what it really means).

[TonyN]

You won't have manual hubs unless a previous owner fitted them, they arn't fitted from new on 2nd Gen Surfs.

If you have them, there is an obvious lock/unlock dial in the hub of the front wheels.

ADD is the way Toyota get round manual hubs, so you can shift in 4wd without stopping or getting out. It's a sliding collar on the long side on the front axle that joins the shaft together when you select 4wd.

When you switch to 4wd 2 things need to happen, first the solonoid on the back of the transfer case switches to drive the front prop, then the collar slids to join the driveshaft on front axle, then the 4WD light comes on on dash.,

[KJT]

fantastic. Thank you for the help.